<template>
  <div>
    <v-chart :data="data" :forceFit="true" :height="height">
      <v-coord direction="LB" type="rect"/>
      <v-tooltip/>
      <v-legend/>
      <v-axis :label="label" dataKey="State"/>
      <v-stack-bar color="流程状态" position="State*流程数量"/>
    </v-chart>
  </div>

</template>

<script>
const DataSet = require('@antv/data-set');

export default {
  name: 'StackBar',
  props: {
    dataSource: {
      type: Array,
      required: true,
      default: () => [
        {'State': '请假', '流转中': 25, '已归档': 18},
        {'State': '出差', '流转中': 30, '已归档': 20},
        {'State': '加班', '流转中': 38, '已归档': 42},
        {'State': '用车', '流转中': 51, '已归档': 67}
      ]
    },
    height: {
      type: Number,
      default: 254
    }
  },
  data() {
    return {
      label: {offset: 12}
    }
  },
  computed: {
    data() {
      const dv = new DataSet.View().source(this.dataSource);
      dv.transform({
        type: 'fold',
        fields: ['流转中', '已归档'],
        key: '流程状态',
        value: '流程数量',
        retains: ['State'],
      });
      return dv.rows;
    }
  }
}
</script>